In my application there are users making pictures of items. The relationship structure is as follows:
Categories -> SubCategories -> Items -> Pictures -> Users
Now, there's also a shortcut relationship called itemPics between categories <--> pictures so that the number of pictures uploaded by a user can be quickly counted per category using withCount().
These are the relationships on the Category model:
public function subcategories()
{
return $this->hasMany('App\SubCategory');
}
public function items()
{
return $this->hasManyThrough('App\Item', 'App\SubCategory');
}
public function itemPics()
{
return $this->hasManyThrough('App\Item', 'App\SubCategory')
->join('pictures','items.id','=','pictures.item_id')
->select('pictures.*');
}
My problem is getting the number of pictures that a user has gathered per category. The itemPics_count column created by withCount() always has the same value as items_count, even though the number of related models for both relations given by with() are different in the JSON output.
$authorPics = Category::with(['SubCategories', 'SubCategories.items' => function ($q) use ($author_id) {
$q->with(['pictures' => function ($q) use ($author_id) {
$q->where('user_id', $author_id);
}]);
}])
->with('itemPics') /* added this to check related models in output */
->withCount(['items','itemPics'])
->get();
dd($authorPics);
This does not make sense to me. Any help is greatly appreciated.
Withcount() function is not work properly if relations include join. it works only table to table relations.
public function itemPics()
{
return $this->hasManyThrough('App\Item', 'App\SubCategory')
->select('pictures.*');
}
This solution was worked for me:
//...
public function itemPics()
{
return $this->hasManyThrough('App\Item', 'App\SubCategory');
}
Then you can do something like this:
$authorPics = Category::with(['SubCategories', 'SubCategories.items' => function ($q) use ($author_id) {
$q->with(['pictures' => function ($q) use ($author_id) {
$q->where('user_id', $author_id);
}]);
}])
->with('itemPics') /* added this to check related models in output */
->withCount(['items','itemPics' => function($query){
$query->join('pictures','items.id','=','pictures.item_id')
->select('pictures.*');
}])
->get();
dd($authorPics);
Link to more information about Laravel withCount function here https://laravel.com/docs/8.x/eloquent-relationships#counting-related-models
Related
Help me please.
I'm trying to write a function where I get all the categories of my forum with the 3 most recently updated Topics in the given categories.
But according to the result, take(3) filters by id (where the id is not higher than 3), and I need to get the last 3 records.
public function index()
{
$forums = Category::with(['posts' => function ($q){
return $q->take(3)->get();
}])->get();
dd($forums);
}
you should order your complete query by update_at descending, only after you can take the first 3.
$q->orderBy('update_at', 'desc')->take(3)->get();
Your Categories table seems to be a different table from posts, so when a post is created or updated you should also set update_at of its category to now.
As far as I know you can not use take() or limit() inside with();
EDIT: solution that was selected by mr.Sardov is to use package staudenmeir/eloquent-eager-limit.
Link is provided below this answer.
So for you need to do is by limit it from model relationship.
For example:
class Category extends Model {
public function posts()
{
return $this->hasMany('App\Models\Post');
}
public function limitPosts()
{
return $this->hasMany('App\Models\Post')
->limit(3);
}
public function limitLatestPosts()
{
return $this->hasMany('App\Models\Post')
->orderBy('created_at', 'desc'). // or use ->latest()
->limit(3);
}
}
And that use it like this:
Category::query()
->with(['limitPosts' => function($query) {
$query->orderBy('created_at', 'desc'); // the last records
}])
->where('id', '<=', 3) // id not higher than 3
->get();
Or
Category::query()
->with('limitLatestPosts')
->where('id', '<=', 3) // id not higher than 3
->get();
Hope this can help you out.
I've spent two days trying to solve this but I can't figure how.
I have five tables
Product
Category
Category_Product
Order
Order_Product
From the view,clicking on a category button I have to fetch all his ordered products with the relative category.
I have the current models:
Product Model
class Product extends Model
{
public function categories() {
return $this->belongsToMany('App\Category');
}
public function orders() {
return $this->belongsTo('App\Order');
}
}
Category Model
public function products() {
return $this->belongsToMany('App\Product');
}
Order Model
public function products() {
return $this->belongsToMany('App\Product');
}
Now the problem is that I can't figure how to fetch the data from the current tables.When I press a button I'm able to fetch the category from the Product Table,but I want to fetch from the Ordered_Products. I really can't figure how.
With this I'm able to fetch all the categories from Product
if (request()->category) {
$products = Product::with('categories')->whereHas('categories', function ($query) {
$query->where('slug', request()->category);
})->get();
}
With this instead,I'm able to fetch the ordered products.
$products = DB::table('order_product')
->join('products', 'order_product.product_id','=', 'products.id')
->where('order_product.user_id','=',$user_id)
->get();
For the latter, there's a better way to do it, that's for sure. I'm sorry if it's a dumb question but I'm rather new with this framework. I am using Laravel 7.2.
Basically Eloquent Model doesn't encourage joining tables to retrieve data. It should be joined only for filtering results (So you need to drop field of other table using ->select('original_table.*'))
In this case, you should simply retrieve categories at first. Then retrieve related data using relation property accessing.
e.g.
$categories = Category::query()
->with('products')
->where('slug', request('category'))
->get();
$products = $categories->flatMap->products;
$pivots = $products->map->pivot;
Solved using whereHas two times:
$products = Product::with('categories')->whereHas('categories',function($query){
$query->where('slug',request()->category);
})->whereHas('orders',function($query){
$query->where('orders.user_id',Auth::id());
})->get();
I have 3 models
User
Channel
Reply
model relations
user have belongsToMany('App\Channel');
channel have hasMany('App\Reply', 'channel_id', 'id')->oldest();
let's say i have 2 channels
- channel-1
- channel-2
channel-2 has latest replies than channel-1
now, i want to order the user's channel by its channel's current reply.
just like some chat application.
how can i order the user's channel just like this?
channel-2
channel-1
i already tried some codes. but nothing happen
// User Model
public function channels()
{
return $this->belongsToMany('App\Channel', 'channel_user')
->withPivot('is_approved')
->with(['replies'])
->orderBy('replies.created_at'); // error
}
// also
public function channels()
{
return $this->belongsToMany('App\Channel', 'channel_user')
->withPivot('is_approved')
->with(['replies' => function($qry) {
$qry->latest();
}]);
}
// but i did not get the expected result
EDIT
also, i tried this. yes i did get the expected result but it would not load all channel if there's no reply.
public function channels()
{
return $this->belongsToMany('App\Channel')
->withPivot('is_approved')
->join('replies', 'replies.channel_id', '=', 'channels.id')
->groupBy('replies.channel_id')
->orderBy('replies.created_at', 'ASC');
}
EDIT:
According to my knowledge, eager load with method run 2nd query. That's why you can't achieve what you want with eager loading with method.
I think use join method in combination with relationship method is the solution. The following solution is fully tested and work well.
// In User Model
public function channels()
{
return $this->belongsToMany('App\Channel', 'channel_user')
->withPivot('is_approved');
}
public function sortedChannels($orderBy)
{
return $this->channels()
->join('replies', 'replies.channel_id', '=', 'channel.id')
->orderBy('replies.created_at', $orderBy)
->get();
}
Then you can call $user->sortedChannels('desc') to get the list of channels order by replies created_at attribute.
For condition like channels (which may or may not have replies), just use leftJoin method.
public function sortedChannels($orderBy)
{
return $this->channels()
->leftJoin('replies', 'channel.id', '=', 'replies.channel_id')
->orderBy('replies.created_at', $orderBy)
->get();
}
Edit:
If you want to add groupBy method to the query, you have to pay special attention to your orderBy clause. Because in Sql nature, Group By clause run first before Order By clause. See detail this problem at this stackoverflow question.
So if you add groupBy method, you have to use orderByRaw method and should be implemented like the following.
return $this->channels()
->leftJoin('replies', 'channels.id', '=', 'replies.channel_id')
->groupBy(['channels.id'])
->orderByRaw('max(replies.created_at) desc')
->get();
Inside your channel class you need to create this hasOne relation (you channel hasMany replies, but it hasOne latest reply):
public function latestReply()
{
return $this->hasOne(\App\Reply)->latest();
}
You can now get all channels ordered by latest reply like this:
Channel::with('latestReply')->get()->sortByDesc('latestReply.created_at');
To get all channels from the user ordered by latest reply you would need that method:
public function getChannelsOrderdByLatestReply()
{
return $this->channels()->with('latestReply')->get()->sortByDesc('latestReply.created_at');
}
where channels() is given by:
public function channels()
{
return $this->belongsToMany('App\Channel');
}
Firstly, you don't have to specify the name of the pivot table if you follow Laravel's naming convention so your code looks a bit cleaner:
public function channels()
{
return $this->belongsToMany('App\Channel') ...
Secondly, you'd have to call join explicitly to achieve the result in one query:
public function channels()
{
return $this->belongsToMany(Channel::class) // a bit more clean
->withPivot('is_approved')
->leftJoin('replies', 'replies.channel_id', '=', 'channels.id') // channels.id
->groupBy('replies.channel_id')
->orderBy('replies.created_at', 'desc');
}
If you have a hasOne() relationship, you can sort all the records by doing:
$results = Channel::with('reply')
->join('replies', 'channels.replay_id', '=', 'replies.id')
->orderBy('replies.created_at', 'desc')
->paginate(10);
This sorts all the channels records by the newest replies (assuming you have only one reply per channel.) This is not your case, but someone may be looking for something like this (as I was.)
My Model Items is related to Rooms, which is related to Buildings, which is related to Locations.
Short: Items belongsTo Rooms belongsTo Buildings belongsTo Locations
At the index function of the ItemController I want to show a table of Items. I use Laravel Datatables. It works for 'simple' tables, but I ran into the problem of sorting/searching custom/appended fields, because they are not in the table of course.
Basically I want to join the Room, Building and Location Name for each Item in the displaying table.
This is my Items Model:
protected $appends = [
'building_title',
'location_title',
'room_title',
];
public function getLocationTitleAttribute() {
return $this->room->building->location->title;
}
public function getBuildingTitleAttribute() {
return $this->room->building->title;
}
public function getRoomTitleAttribute() {
return $this->room->title;
}
This is my Controller:
public function anyData()
{
return Datatables::of(Item::query())->make(true);
}
What is the best approach to enable sorting/filtering for appended fields?
Thank you for reading.
This is my solution (no appended fields were used):
public function anyData()
{
$items = Item::join('rooms', 'items.room_id', '=', 'rooms.id')
->join('buildings', 'rooms.building_id', '=', 'buildings.id')
->join('locations', 'buildings.location_id', '=', 'locations.id')
->select([
'items.id',
'items.title',
'items.label_number',
'items.fibu_number',
'rooms.title as room_title',
'buildings.title as building_title',
'locations.title as location_title'
]);
return Datatables::of($items)->make(true);
}
In the documentation of Eloquent it is said that I can pass the keys of a desired relationship to hasManyThrough.
Lets say I have Models named Country, User, Post. A Country model might have many Posts through a Users model. That said I simply could call:
$this->hasManyThrough('Post', 'User', 'country_id', 'user_id');
This is fine so far! But how can I get these posts only for the user with the id of 3 ?
Can anybody help here?
So here it goes:
models: Country has many User has many Post
This allows us to use hasManyThrough like in your question:
// Country model
public function posts()
{
return $this->hasManyThrough('Post', 'User', 'country_id', 'user_id');
}
You want to get posts of a given user for this relation, so:
$country = Country::first();
$country->load(['posts' => function ($q) {
$q->where('user_id', '=', 3);
}]);
// or
$country->load(['posts' => function ($q) {
$q->has('user', function ($q) {
$q->where('users.id', '=', 3);
});
})
$country->posts; // collection of posts related to user with id 3
BUT it will be easier, more readable and more eloquent if you use this instead:
(since it has nothing to do with country when you are looking for the posts of user with id 3)
// User model
public function posts()
{
return $this->hasMany('Post');
}
// then
$user = User::find(3);
// lazy load
$user->load('posts');
// or use dynamic property
$user->posts; // it will load the posts automatically
// or eager load
$user = User::with('posts')->find(3);
$user->posts; // collection of posts for given user
To sum up: hasManyThrough is a way to get nested relation directly, ie. all the posts for given country, but rather not to search for specific through model.
$user_id = 3;
$country = Country::find($country_id);
$country->posts()->where('users.id', '=', $user_id)->get();
$this->hasManyThrough('Post', 'User', 'country_id', 'user_id')->where(column,x);
What happen here is you get the collection in return you can put any condition you want at the end.